Support and stretching mechanism for motion picture screens



2 Sheets-Sheet l IN VEN TOR.

afi ATTOR EYS.

P. HANSEN Filed March 6, 1951 v N d076 QWW W Q in SUPPORT AND STRETCHINGMECHANISM FOR MOTION PICTURE SCREENS March 21, 1933.-

March 21, 1933. J. P. HANSEN 1,901,

SUPPORT AND S'IRETCI'IIIflC MECHANISM FOR MOTION PICTURE SCREENS FiledMarch 6, 1931 2 Sheets-Sheet 2 INVENTOR. MW

w i Ma 3K Patented Mar. 21, 1933 Y v UNITED STATES PATENT OFFICE JOHN P.HANSEN, F ELMHUBST, NEW YORK Application filed larch 6,

' My invention relates to an improved support and stretching mechanismfor motion picture screens.

'At the present time motion picture screens are supported on frame-Workto which they are laced by means of ropes or cables. When it is desiredto stretch screens thus supported all the stretching must be done bytightening upon the ropes. For this reason it is neces- 0 sary forworkmen to climb the frame-work for the purpose of lacing the screen tothe support and also when tightening the ropes in stretching thescreenwith the ever constant danger of workmen falling.

It-is one of the objects of my invention to provide a combined supportand stretcher for motion picture screens whereby the securing of thescreen to the support and all stretching of the screen is accomplishedby the workmen on the stage without the necessity or danger of climbingthe frame-work.

Another object of my invention is the provision of a device wherebytheinstalling and stretching of the screen is accomplished with comparativeease and a considerable saving in time and labor.

Further objects of my invention will be manifest from the followingdescription and the accompanying drawings in which Fig. 1 is anelevational view of my improved device;

Fig. 2 is a sectional View on line 2-2 of Fig. 1

Fig. 3 is a sectional view on line 3-3 of Fi 1;

Fig. 4 is a sectional view on line 44 of Fig. 1;

Fig. 5 is an enlarged view of the hoisting mechanism, and

Fig. 6 is a sectional view showing a modified form of sliding hook forthe screen.

Referring to the drawings in detail 1 designates a stage on which restssupporting lattice frame-work comprising stationary vertical posts 2 and3 and stationary overhead beam 4. A movable horizontal frame 5 issuspended from the overhead beam 4 by means of ropes 6 secured to theframe 5 and passing over a plurality of pulleys 7 secured to theoverhead beam 4 and thence to the side of the 1931. Serial No. 520,736.

frame-work and over a pulley. 8 Where-the ropes are secured to a coupler9. The coupler 9 has one end of a rope 10 secured thereto, the other endbeing secured wound about a drum or Windlass 11. The Windlass 11 ismounted upon a bracket 12 secured to the vertical post 3 and is adaptedto be rotated by means of a crank handle 13 through gears 14 and15, apawl 16 and ratchet 17 being provided to prevent the unwinding oftherope.

The movable frame 5 is in the form of a horizontally extending boxhaving a plurality of covers 18 hinged thereto for convenience ofaccessibility and is provided at each of its extremities with rollers 19and 20 which are adapted to ride on the outside of stationary verticalboxes 21 and 22 respectively rigidly secured to the vertical posts 2 and3 respectively of the frame-work by means of bars or brackets 23.

Each of the vertical boxes 21 and 22 and the mechanism enclosed in eachis similar hence only one of these will be herein described.

Within each of the vertical boxes 21 and 22 a longitudinal shaft 24 isprovided having a beveled gear 25 at its lower extremity in engagementwith another beveled gear 26 on crank shaft 27, which shaft is adaptedto be rotated by means of a crank handle 28. On this shaft 27 there isalso provided a pawl and ratchet arrangement 29 for locking the sameagainst reverse rotation. The longitudinal shaft 24 is provided alsowith a plurality of spaced gears 30 adapted to engage a correspondingnumber of racks 31 which are mounted for lateral movement within the boxand carry a vertical bar 32. This bar 32 may be in the form of a channelhaving a longitudinal opening or slot 33 in one wall thereof adapted toreceive sliding hooks 34 which may be either in the form shown in Fig. 3or that shown in Fig. 6, these hooks being adapted to slide verticallyin the channel as will be hereinafter explained.

The horizontal movable frame 5 is pro vided with a bar 35 which extendslongitudinally thereof and has a plurality of hooks 36 to and adapted tobe pivotally secured thereto by. means of 36 by passing grommets 13 inthe screen over said hooks. The frame 5 is then hoisted by rotating thecrank handle 13 and as the frame 7 is being raised the grommets in thevertical prising vertically extending edges or sides of the screen aresecured progressively in order to their respective hooks 34; on thevertical bars 32 until the screen has been completely raised andall ofthe grommets have been attached. The grommets along the lower edgeof thescreen are then secured to the hooks ll on the bar 40.

The screen is now in position to be stretched and vertical stretching isaccomplished by continuing the rotation of the crank handle 13.Transverse stretching is accomplished by rotation of the crank handles28 upon rotation of which it will be obvious that the racks 31 will bemoved laterally, carrying with them the Vertical bars at to which thescreen is secured as above pointed out.

It will be seen from the foregoing, therefore,that I have provided ascreen supporting and stretching apparatus so constructed and arrangedthatall mounting and stretching of the screen can be done from the stagethereby, as above pointed out, eliminating the necessity of the workmenclimbing the frame-work and running the risk of falling. It will beappreciated also that a more uniform stretching of the screen is obtainethan by the use of prior apparatus, thus insuring a smooth, taut screenwhich is exceedingl desirable in motion picture projection. I v

It is to be understood that I do not wish to be limited to the precisestructure herein illustrated and described inasmuch as variousmodifications may be made therein without departing from the spirit andscope of my invention.

What I claim is: a

1. A device of the class described combars, vertically sliding hooks onsaid bars for securing a motion picture screen thereto, and means formoving said bars laterally to stretch said screen.

2. A device of the class described com;- prising a pair of verticalchannel members, hooks carried by and movable lengthwise of said channelmembers, a motion picture screen carried by said hooks, means for ablebar withineach moving said channel members laterally to stretch saidscreen.

3. In a device of the class described the combination of vertical bars,vertically sliding hooks on said bars for attaching the side edges of amotion picture screen thereto, means for moving said bars laterally toeffect lateral stretching'bf the screen, a horizontally extending bar,means for attaching the upper edge of a motion picture screen thereto,said last-mentioned bar being movable vertically with respect to saidvertically extending bars to effect vertical stretching of the screen.

4. A' device ofthe class described comprising vertically extending bars,means movable longitudinally of said vertically extending bars forsecuring the side edges of a motion picture screen thereto, means formoving said bars to stretch the screen laterally, a horizontallyextending bar, means for securing the upper edge of the motion picturescreen thereto, and meansfor raisin g said bar to stretch the screenvertically.

5. A device of the class described comprising in combination a pair ofstationary vertically extending. housings, a laterally movof saidhousings, means carried by each bar for attachingthe side edges of amotion picture screen I thereto, means for adjusting said barlaterally'to effect lateral stretching of the screen, each of saidhousings being provided in the wall ad jacent the edge of the screenwith a continuous slot for the accommodation of the edge of the screenupon lateral stretching of the screen, i

This specification signed this 13th day of February, 1931,

. JOHN P. HANSEN.

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